[+cc Rafael, Len, linux-acpi] On Sat, Oct 27, 2018 at 12:09:10PM -0300, Elie Morisse wrote: > This contains two drivers: > * i2c-amd-plat-mp2: platform driver managing an i2c adapter (one of > the two busses of the MP2) and routing any i2c read/write command to > the PCI driver. > * i2c-amd-pci-mp2: PCI driver communicating through the C2P/P2C > mailbox registers, or through DMA for more than 32 bytes transfers.
I'm dubious about this two-driver structure. If I understand correctly (and it's very possible that I don't), the PCI driver (amd_mp2_pci_probe()) is the real owner of the i2c adapter: it claims the PCI device, claims its BARs, and requests an IRQ. The i2c_amd_probe() code *looks* like a platform driver that claims AMDI0011 devices from the ACPI namespace, but I don't think it's really a driver. It looks like it exists mainly to extract some information (bus speed and maybe a bus number?) from the namespace, then to call i2c_add_adapter(). It looks like i2c_amd_probe() must run *after* amd_mp2_pci_probe(), but there's no way to really enforce that ordering. And i2c-amd-plat-mp2 contains the i2c_amd_algorithm functions, which operate on the PCI device, which requires exported interfaces (amd_mp2_read(), amd_mp2_write()) that are implemented in the PCI driver but called from the platform part. It seems like there should be a way to put the ACPI lookups into i2c-amd-pci-mp2 so there's only one driver. I only have a couple trivial comments below but I'm not trimming my response so the ACPI folks can see the whole context. > This is major rework of the patch submitted by Nehal-bakulchandra Shah > from AMD (https://patchwork.kernel.org/patch/10597369/). > > Most of the event handling of v2/v3 was rewritten since it couldn't work > if more than one bus was enabled, and contains many more fixes listed > in the patch changelog. > > With those changes both the touchpad and the touchscreen of the > Ryzen-based Lenovo Yoga 530 which lie in separate busses work beautifully. > > Signed-off-by: Elie Morisse <syniu...@gmail.com> > --- > Changes since v1:(https://www.spinics.net/lists/linux-i2c/msg34650.html) > -> Add fix for IOMMU > -> Add depedency of ACPI > -> Add locks to avoid the crash > > Changes since v2:(https://patchwork.ozlabs.org/patch/961270/) > > -> fix for review comments > -> fix for more than 32 bytes write issue > > Changes since v3 (https://patchwork.kernel.org/patch/10597369/) by Elie M.: > > -> support more than one bus/adapter > -> support more than one slave per bus > -> use the bus speed specified by the slaves declared in the DSDT instead of > assuming speed == 400kbits/s > -> instead of kzalloc'ing a buffer for every less than 32 bytes reads, simply > use i2c_msg.buf > -> fix buffer overreads/overflows when (<=32 bytes) message lengths aren't a > multiple of 4 by using memcpy_fromio and memcpy_toio > -> use streaming DMA mappings instead of allocating a coherent DMA buffer for > every >32 bytes read/write > -> properly check for timeouts during i2c_amd_xfer and increase it from 50 > jiffies to 250 msecs (which is more in line with other drivers) > -> complete amd_i2c_dev.msg even if the device doesn't return a xxx_success > event, instead of stalling i2c_amd_xfer > -> removed the spinlock and mdelay during i2c_amd_pci_configure, I didn't see > the point since it's already waiting for a i2c_busenable_complete event > -> add an adapter-specific mutex lock for i2c_amd_xfer, since we don't want > parallel calls writing to AMD_C2P_MSG0 (or AMD_C2P_MSG1) > -> add a global mutex lock for registers AMD_C2P_MSG2 to AMD_C2P_MSG9, which > are shared across the two busses/adapters > -> add MODULE_DEVICE_TABLE to automatically load i2c-amd-platdrv if the DSDT > enumerates devices with the "AMDI0011" HID > -> set maximum length of reads/writes to 4095 (event's length field is 12 > bits) > -> basic PM support > -> style corrections to match the kernel code style, and tried to reduce code > duplication whenever possible > > Changes since v4 (https://marc.info/?l=linux-kernel&m=154031133019835) by > Elie M.: > > -> fix missing typecast warning > -> removed the duplicated entry in Kconfig > > Changes since v5 by Elie M.: > > -> move DMA mapping from the platform driver to the PCI driver > -> attempt to find the platform device's PCI parent through the _DEP ACPI > method > (if not found take the first MP2 device registred in the i2c-amd-pci-mp2 > driver, like before) > -> do not assume anymore that the PCI device is owned by the i2c-amd-pci-mp2 > driver > -> address other review comments by Bjorn Helgaas (meant for v3) > > Changes since v6 by Elie M.: > > -> remove unnecessary memcpy from the DMA buffer during > i2c_amd_read_completion > > MAINTAINERS | 6 + > drivers/i2c/busses/Kconfig | 15 + > drivers/i2c/busses/Makefile | 2 + > drivers/i2c/busses/i2c-amd-pci-mp2.c | 706 ++++++++++++++++++++++++++ > drivers/i2c/busses/i2c-amd-pci-mp2.h | 224 ++++++++ > drivers/i2c/busses/i2c-amd-plat-mp2.c | 373 ++++++++++++++ > 6 files changed, 1326 insertions(+) > create mode 100644 drivers/i2c/busses/i2c-amd-pci-mp2.c > create mode 100644 drivers/i2c/busses/i2c-amd-pci-mp2.h > create mode 100644 drivers/i2c/busses/i2c-amd-plat-mp2.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 6ac000cc006d..8ff2bddc1ac2 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -791,6 +791,12 @@ F: drivers/gpu/drm/amd/include/vi_structs.h > F: drivers/gpu/drm/amd/include/v9_structs.h > F: include/uapi/linux/kfd_ioctl.h > > +AMD MP2 I2C DRIVER > +M: Elie Morisse <syniu...@gmail.com> > +L: linux-...@vger.kernel.org > +S: Maintained > +F: drivers/i2c/busses/i2c-amd-*-mp2* > + > AMD POWERPLAY > M: Rex Zhu <rex....@amd.com> > M: Evan Quan <evan.q...@amd.com> > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > index 451d4ae50e66..e20f2d1ce381 100644 > --- a/drivers/i2c/busses/Kconfig > +++ b/drivers/i2c/busses/Kconfig > @@ -77,6 +77,21 @@ config I2C_AMD8111 > This driver can also be built as a module. If so, the module > will be called i2c-amd8111. > > +config I2C_AMD_MP2_PCI > + tristate > + depends on PCI > + > +config I2C_AMD_MP2_PLATFORM > + tristate "AMD MP2 Platform" > + select I2C_AMD_MP2_PCI > + depends on ACPI > + help > + If you say yes to this option, support will be included for the AMD > MP2 > + PCI I2C adapter. > + > + This driver can also be built as a module. If so, the module > + will be called i2c-amd-plat-mp2. > + > config I2C_HIX5HD2 > tristate "Hix5hd2 high-speed I2C driver" > depends on ARCH_HISI || ARCH_HIX5HD2 || COMPILE_TEST > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > index 18b26af82b1c..16ef646d7ef5 100644 > --- a/drivers/i2c/busses/Makefile > +++ b/drivers/i2c/busses/Makefile > @@ -32,6 +32,8 @@ obj-$(CONFIG_I2C_POWERMAC) += i2c-powermac.o > > # Embedded system I2C/SMBus host controller drivers > obj-$(CONFIG_I2C_ALTERA) += i2c-altera.o > +obj-$(CONFIG_I2C_AMD_MP2_PCI) += i2c-amd-pci-mp2.o > +obj-$(CONFIG_I2C_AMD_MP2_PLATFORM) += i2c-amd-plat-mp2.o > obj-$(CONFIG_I2C_ASPEED) += i2c-aspeed.o > obj-$(CONFIG_I2C_AT91) += i2c-at91.o > obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o > diff --git a/drivers/i2c/busses/i2c-amd-pci-mp2.c > b/drivers/i2c/busses/i2c-amd-pci-mp2.c > new file mode 100644 > index 000000000000..eb54825f3f69 > --- /dev/null > +++ b/drivers/i2c/busses/i2c-amd-pci-mp2.c > @@ -0,0 +1,706 @@ > +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause > +/* > + * AMD PCIe MP2 Communication Driver > + * > + * Authors: Shyam Sundar S K <shyam-sundar....@amd.com> > + * Elie Morisse <syniu...@gmail.com> > + */ > + > +#include <linux/debugfs.h> > +#include <linux/dma-mapping.h> > +#include <linux/interrupt.h> > +#include <linux/module.h> > +#include <linux/pci.h> > +#include <linux/slab.h> > + > +#include "i2c-amd-pci-mp2.h" > + > +#define DRIVER_NAME "pcie_mp2_amd" > +#define DRIVER_DESC "AMD(R) PCI-E MP2 Communication Driver" > +#define DRIVER_VER "1.0" > + > +static const struct file_operations amd_mp2_debugfs_info; > +static struct dentry *debugfs_dir; > + > +#define write64 _write64 > +static inline void _write64(u64 val, void __iomem *mmio) > +{ > + writel(val, mmio); > + writel(val >> 32, mmio + sizeof(u32)); > +} > + > +#define read64 _read64 > +static inline u64 _read64(void __iomem *mmio) > +{ > + u64 low, high; > + > + low = readl(mmio); > + high = readl(mmio + sizeof(u32)); > + return low | (high << 32); > +} > + > +static int amd_mp2_cmd(struct amd_mp2_dev *privdata, > + union i2c_cmd_base i2c_cmd_base) > +{ > + void __iomem *reg; > + > + if (i2c_cmd_base.s.bus_id > 1) { > + dev_err(ndev_dev(privdata), "%s Invalid bus id\n", __func__); > + return -EINVAL; > + } > + > + reg = privdata->mmio + ((i2c_cmd_base.s.bus_id == 1) ? > + AMD_C2P_MSG1 : AMD_C2P_MSG0); > + writel(i2c_cmd_base.ul, reg); > + > + return 0; > +} > + > +int amd_mp2_connect(struct amd_i2c_common *i2c_common, bool enable) > +{ > + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; > + union i2c_cmd_base i2c_cmd_base; > + > + dev_dbg(ndev_dev(privdata), "%s id: %d\n", __func__, > + i2c_common->bus_id); > + > + i2c_common->reqcmd = enable ? i2c_enable : i2c_disable; > + > + i2c_cmd_base.ul = 0; > + i2c_cmd_base.s.i2c_cmd = i2c_common->reqcmd; > + i2c_cmd_base.s.bus_id = i2c_common->bus_id; > + i2c_cmd_base.s.i2c_speed = i2c_common->i2c_speed; > + > + return amd_mp2_cmd(privdata, i2c_cmd_base); > +} > +EXPORT_SYMBOL_GPL(amd_mp2_connect); > + > +static void amd_mp2_cmd_rw_fill(struct amd_i2c_common *i2c_common, > + union i2c_cmd_base *i2c_cmd_base, > + enum i2c_cmd reqcmd) > +{ > + i2c_common->reqcmd = reqcmd; > + > + i2c_cmd_base->s.i2c_cmd = reqcmd; > + i2c_cmd_base->s.bus_id = i2c_common->bus_id; > + i2c_cmd_base->s.i2c_speed = i2c_common->i2c_speed; > + i2c_cmd_base->s.slave_addr = i2c_common->rw_cfg.slave_addr; > + i2c_cmd_base->s.length = i2c_common->rw_cfg.length; > +} > + > +static int amd_mp2_dma_map(struct amd_mp2_dev *privdata, > + struct amd_i2c_common *i2c_common, > + bool is_write) > +{ > + enum dma_data_direction dma_direction = is_write ? > + DMA_TO_DEVICE : DMA_FROM_DEVICE; > + > + i2c_common->rw_cfg.dma_addr = dma_map_single(&privdata->pci_dev->dev, > + i2c_common->rw_cfg.buf, > + i2c_common->rw_cfg.length, > + dma_direction); > + i2c_common->rw_cfg.dma_direction = dma_direction; > + > + if (dma_mapping_error(&privdata->pci_dev->dev, > + i2c_common->rw_cfg.dma_addr)) { > + dev_err(ndev_dev(privdata), > + "Error while mapping dma buffer %p\n", > + i2c_common->rw_cfg.buf); > + return -EIO; > + } > + > + return 0; > +} > + > +static void amd_mp2_dma_unmap(struct amd_mp2_dev *privdata, > + struct amd_i2c_common *i2c_common) > +{ > + dma_unmap_single(&privdata->pci_dev->dev, > + i2c_common->rw_cfg.dma_addr, > + i2c_common->rw_cfg.length, > + i2c_common->rw_cfg.dma_direction); > +} > + > +int amd_mp2_read(struct amd_i2c_common *i2c_common) > +{ > + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; > + union i2c_cmd_base i2c_cmd_base; > + > + dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__, > + i2c_common->rw_cfg.slave_addr, i2c_common->bus_id); > + > + amd_mp2_cmd_rw_fill(i2c_common, &i2c_cmd_base, i2c_read); > + > + /* there is only one data mailbox for two i2c adapters */ > + mutex_lock(&privdata->c2p_lock); > + > + if (!i2c_common->rw_cfg.buf) { > + dev_err(ndev_dev(privdata), "%s no mem for buf received\n", > + __func__); > + return -ENOMEM; > + } > + > + if (i2c_common->rw_cfg.length <= 32) { > + i2c_cmd_base.s.mem_type = use_c2pmsg; > + } else { > + i2c_cmd_base.s.mem_type = use_dram; > + if (amd_mp2_dma_map(privdata, i2c_common, false)) > + return -EIO; > + write64((u64)i2c_common->rw_cfg.dma_addr, > + privdata->mmio + AMD_C2P_MSG2); > + } > + > + return amd_mp2_cmd(privdata, i2c_cmd_base); > +} > +EXPORT_SYMBOL_GPL(amd_mp2_read); > + > +int amd_mp2_write(struct amd_i2c_common *i2c_common) > +{ > + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; > + union i2c_cmd_base i2c_cmd_base; > + > + dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__, > + i2c_common->rw_cfg.slave_addr, i2c_common->bus_id); > + > + amd_mp2_cmd_rw_fill(i2c_common, &i2c_cmd_base, i2c_write); > + > + /* there is only one data mailbox for two i2c adapters */ > + mutex_lock(&privdata->c2p_lock); > + > + if (i2c_common->rw_cfg.length <= 32) { > + i2c_cmd_base.s.mem_type = use_c2pmsg; > + memcpy_toio(privdata->mmio + AMD_C2P_MSG2, > + i2c_common->rw_cfg.buf, > + i2c_common->rw_cfg.length); > + } else { > + i2c_cmd_base.s.mem_type = use_dram; > + if (amd_mp2_dma_map(privdata, i2c_common, true)) > + return -EIO; > + write64((u64)i2c_common->rw_cfg.dma_addr, > + privdata->mmio + AMD_C2P_MSG2); > + } > + > + return amd_mp2_cmd(privdata, i2c_cmd_base); > +} > +EXPORT_SYMBOL_GPL(amd_mp2_write); > + > +static void amd_mp2_pci_do_work(struct work_struct *work) > +{ > + struct amd_i2c_common *i2c_common = work_amd_i2c_common(work); > + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; > + int sts = i2c_common->eventval.r.status; > + int res = i2c_common->eventval.r.response; > + int len = i2c_common->eventval.r.length; > + u32 slave_addr = i2c_common->eventval.r.slave_addr; > + > + if (len != i2c_common->rw_cfg.length) > + dev_err(ndev_dev(privdata), > + "length %d in event doesn't match buffer length %d!\n", > + len, i2c_common->rw_cfg.length); > + if (slave_addr != i2c_common->rw_cfg.slave_addr) > + dev_err(ndev_dev(privdata), > + "unexpected slave address %x (expected: %x)!\n", > + slave_addr, i2c_common->rw_cfg.slave_addr); > + > + if (res != command_success) { > + if (res == command_failed) > + dev_err(ndev_dev(privdata), "i2c command failed!\n"); > + else > + dev_err(ndev_dev(privdata), "invalid response to i2c > command!\n"); > + return; > + } > + > + switch (i2c_common->reqcmd) { > + case i2c_read: > + if (sts == i2c_readcomplete_event) { > + if (len <= 32) > + memcpy_fromio(i2c_common->rw_cfg.buf, > + privdata->mmio + AMD_C2P_MSG2, > + i2c_common->rw_cfg.length); > + } else if (sts == i2c_readfail_event) { > + dev_err(ndev_dev(privdata), "i2c read failed!\n"); > + } else { > + dev_err(ndev_dev(privdata), "invalid i2c status after > read!\n"); > + } > + > + i2c_common->ops->read_complete(&i2c_common->eventval); > + break; > + case i2c_write: > + if (sts == i2c_writefail_event) > + dev_err(ndev_dev(privdata), "i2c write failed!\n"); > + else if (sts != i2c_writecomplete_event) > + dev_err(ndev_dev(privdata), "invalid i2c status after > write!\n"); > + > + i2c_common->ops->write_complete(&i2c_common->eventval); > + break; > + case i2c_enable: > + if (sts == i2c_busdisable_failed) > + dev_err(ndev_dev(privdata), "i2c bus enable failed!\n"); > + else if (sts != i2c_busenable_complete) > + dev_err(ndev_dev(privdata), "invalid i2c status after > bus enable!\n"); > + > + i2c_common->ops->connect_complete(&i2c_common->eventval); > + break; > + default: > + break; > + } > + > + if ((i2c_common->reqcmd == i2c_read || > + i2c_common->reqcmd == i2c_write) && > + i2c_common->rw_cfg.length > 32) > + amd_mp2_dma_unmap(privdata, i2c_common); > +} > + > +static void amd_mp2_pci_work(struct work_struct *work) > +{ > + struct amd_i2c_common *i2c_common = work_amd_i2c_common(work); > + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; > + enum i2c_cmd cmd = i2c_common->reqcmd; > + > + amd_mp2_pci_do_work(work); > + > + i2c_common->reqcmd = i2c_none; > + > + if (cmd == i2c_read || cmd == i2c_write) > + mutex_unlock(&privdata->c2p_lock); > +} > + > +static irqreturn_t amd_mp2_irq_isr(int irq, void *dev) > +{ > + struct amd_mp2_dev *privdata = dev; > + struct amd_i2c_common *i2c_common; > + u32 val; > + unsigned int bus_id; > + void __iomem *reg; > + unsigned long flags; > + enum irqreturn ret = IRQ_NONE; > + > + raw_spin_lock_irqsave(&privdata->lock, flags); > + > + for (bus_id = 0; bus_id < 2; bus_id++) { > + reg = privdata->mmio + ((bus_id == 0) ? > + AMD_P2C_MSG1 : AMD_P2C_MSG2); > + val = readl(reg); > + if (val != 0) { > + i2c_common = privdata->plat_common[bus_id]; > + if (!i2c_common) > + continue; > + i2c_common->eventval.ul = val; > + > + writel(0, reg); > + writel(0, privdata->mmio + AMD_P2C_MSG_INTEN); > + > + if (i2c_common->reqcmd != i2c_none) > + schedule_delayed_work(&i2c_common->work, 0); > + > + ret = IRQ_HANDLED; > + } > + } > + > + raw_spin_unlock_irqrestore(&privdata->lock, flags); > + return ret; > +} > + > +int amd_i2c_register_cb(struct amd_mp2_dev *privdata, > + struct amd_i2c_common *i2c_common) > +{ > + if (i2c_common->bus_id > 1) > + return -EINVAL; > + privdata->plat_common[i2c_common->bus_id] = i2c_common; > + > + INIT_DELAYED_WORK(&i2c_common->work, amd_mp2_pci_work); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(amd_i2c_register_cb); > + > +int amd_i2c_unregister_cb(struct amd_mp2_dev *privdata, > + struct amd_i2c_common *i2c_common) > +{ > + cancel_delayed_work_sync(&i2c_common->work); > + privdata->plat_common[i2c_common->bus_id] = NULL; > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(amd_i2c_unregister_cb); > + > +static ssize_t amd_mp2_debugfs_read(struct file *filp, char __user *ubuf, > + size_t count, loff_t *offp) > +{ > + struct amd_mp2_dev *privdata; > + void __iomem *mmio; > + u8 *buf; > + size_t buf_size; > + ssize_t ret, off; > + u32 v32; > + > + privdata = filp->private_data; > + mmio = privdata->mmio; > + buf_size = min_t(size_t, count, 0x800); > + buf = kmalloc(buf_size, GFP_KERNEL); > + > + if (!buf) > + return -ENOMEM; > + > + off = 0; > + off += scnprintf(buf + off, buf_size - off, > + "Mp2 Device Information:\n"); > + > + off += scnprintf(buf + off, buf_size - off, > + "========================\n"); > + off += scnprintf(buf + off, buf_size - off, > + "\tMP2 C2P Message Register Dump:\n\n"); > + v32 = readl(privdata->mmio + AMD_C2P_MSG0); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG0 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG1); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG1 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG2); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG2 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG3); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG3 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG4); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG4 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG5); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG5 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG6); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG6 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG7); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG7 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG8); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG8 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_C2P_MSG9); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_C2P_MSG9 -\t\t\t%#06x\n", v32); > + > + off += scnprintf(buf + off, buf_size - off, > + "\n\tMP2 P2C Message Register Dump:\n\n"); > + > + v32 = readl(privdata->mmio + AMD_P2C_MSG1); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_P2C_MSG1 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_P2C_MSG2); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_P2C_MSG2 -\t\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_P2C_MSG_INTEN); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_P2C_MSG_INTEN -\t\t%#06x\n", v32); > + > + v32 = readl(privdata->mmio + AMD_P2C_MSG_INTSTS); > + off += scnprintf(buf + off, buf_size - off, > + "AMD_P2C_MSG_INTSTS -\t\t%#06x\n", v32); > + > + ret = simple_read_from_buffer(ubuf, count, offp, buf, off); > + kfree(buf); > + return ret; > +} > + > +static void amd_mp2_init_debugfs(struct amd_mp2_dev *privdata) > +{ > + if (!debugfs_dir) { > + privdata->debugfs_dir = NULL; > + privdata->debugfs_info = NULL; > + return; > + } > + > + privdata->debugfs_dir = debugfs_create_dir(ndev_name(privdata), > + debugfs_dir); > + if (!privdata->debugfs_dir) { > + privdata->debugfs_info = NULL; > + } else { > + privdata->debugfs_info = debugfs_create_file > + ("info", 0400, privdata->debugfs_dir, > + privdata, &amd_mp2_debugfs_info); > + } > +} > + > +static void amd_mp2_deinit_debugfs(struct amd_mp2_dev *privdata) > +{ > + debugfs_remove_recursive(privdata->debugfs_dir); > +} > + > +static void amd_mp2_clear_reg(struct amd_mp2_dev *privdata) > +{ > + int reg; > + > + for (reg = AMD_C2P_MSG0; reg <= AMD_C2P_MSG9; reg += 4) > + writel(0, privdata->mmio + reg); > + > + for (reg = AMD_P2C_MSG0; reg <= AMD_P2C_MSG2; reg += 4) > + writel(0, privdata->mmio + reg); > +} > + > +static int amd_mp2_pci_init(struct amd_mp2_dev *privdata, > + struct pci_dev *pci_dev) > +{ > + int rc; > + resource_size_t size, base; > + > + pci_set_drvdata(pci_dev, privdata); > + > + rc = pci_enable_device(pci_dev); > + if (rc) > + goto err_pci_enable; > + > + rc = pci_request_regions(pci_dev, DRIVER_NAME); > + if (rc) > + goto err_pci_regions; > + > + pci_set_master(pci_dev); > + > + rc = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(64)); > + if (rc) { > + rc = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(32)); > + if (rc) > + goto err_dma_mask; > + dev_warn(ndev_dev(privdata), "Cannot DMA highmem\n"); > + } > + > + rc = pci_set_consistent_dma_mask(pci_dev, DMA_BIT_MASK(64)); > + if (rc) { > + rc = pci_set_consistent_dma_mask(pci_dev, DMA_BIT_MASK(32)); > + if (rc) > + goto err_dma_mask; > + dev_warn(ndev_dev(privdata), "Cannot DMA consistent highmem\n"); > + } > + > + base = pci_resource_start(pci_dev, 2); > + size = pci_resource_len(pci_dev, 2); > + dev_dbg(ndev_dev(privdata), "Base addr:%zx size:%zx\n", > + (size_t)base, (size_t)size); You can use %pR on pci_dev->resource[2]. That uses the conventional format (same as used by the PCI core). > + > + mutex_init(&privdata->c2p_lock); > + privdata->mmio = ioremap(base, size); > + if (!privdata->mmio) { > + rc = -EIO; > + goto err_dma_mask; > + } > + > + /* Try to set up intx irq */ > + raw_spin_lock_init(&privdata->lock); > + pci_intx(pci_dev, 1); > + rc = request_irq(pci_dev->irq, amd_mp2_irq_isr, IRQF_SHARED, > + "mp2_irq_isr", privdata); > + if (rc) > + goto err_intx_request; > + > + return 0; > + > +err_intx_request: > + return rc; > +err_dma_mask: > + pci_clear_master(pci_dev); > + pci_release_regions(pci_dev); > +err_pci_regions: > + pci_disable_device(pci_dev); > +err_pci_enable: > + pci_set_drvdata(pci_dev, NULL); > + return rc; > +} > + > +static void amd_mp2_pci_deinit(struct amd_mp2_dev *privdata) > +{ > + struct pci_dev *pci_dev = ndev_pdev(privdata); > + > + pci_iounmap(pci_dev, privdata->mmio); > + > + pci_clear_master(pci_dev); > + pci_release_regions(pci_dev); > + pci_disable_device(pci_dev); > + pci_set_drvdata(pci_dev, NULL); > +} > + > +static int amd_mp2_pci_probe(struct pci_dev *pci_dev, > + const struct pci_device_id *id) > +{ > + struct amd_mp2_dev *privdata; > + int rc; > + static bool first_probe = true; > + > + if (first_probe) { > + pr_info("%s: %s Version: %s\n", DRIVER_NAME, > + DRIVER_DESC, DRIVER_VER); > + first_probe = false; > + } > + > + dev_info(&pci_dev->dev, "MP2 device found [%04x:%04x] (rev %x)\n", > + (int)pci_dev->vendor, (int)pci_dev->device, > + (int)pci_dev->revision); > + > + privdata = kzalloc(sizeof(*privdata), GFP_KERNEL); > + if (!privdata) { > + rc = -ENOMEM; > + goto err_dev; There's nothing to clean up at this point, so just emit the message and return directly: if (!privdata) { dev_err(&pci_dev->dev, "Memory Allocation Failed\n"); return -ENOMEM; } > + } > + > + privdata->pci_dev = pci_dev; > + > + rc = amd_mp2_pci_init(privdata, pci_dev); > + if (rc) > + goto err_pci_init; > + dev_dbg(&pci_dev->dev, "pci init done.\n"); > + > + amd_mp2_init_debugfs(privdata); > + dev_info(&pci_dev->dev, "MP2 device registered.\n"); > + return 0; > + > +err_pci_init: > + kfree(privdata); > +err_dev: > + dev_err(&pci_dev->dev, "Memory Allocation Failed\n"); > + return rc; > +} > + > +static void amd_mp2_pci_remove(struct pci_dev *pci_dev) > +{ > + struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev); > + unsigned int bus_id; > + > + for (bus_id = 0; bus_id < 2; bus_id++) > + if (privdata->plat_common[bus_id]) > + amd_i2c_unregister_cb(privdata, > + privdata->plat_common[bus_id]); > + > + amd_mp2_deinit_debugfs(privdata); > + amd_mp2_clear_reg(privdata); > + free_irq(pci_dev->irq, privdata); > + pci_intx(pci_dev, 0); > + amd_mp2_pci_deinit(privdata); > + kfree(privdata); > +} > + > +static const struct file_operations amd_mp2_debugfs_info = { > + .owner = THIS_MODULE, > + .open = simple_open, > + .read = amd_mp2_debugfs_read, > +}; > + > +static const struct pci_device_id amd_mp2_pci_tbl[] = { > + {PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_MP2)}, > + {0} > +}; > +MODULE_DEVICE_TABLE(pci, amd_mp2_pci_tbl); > + > +#ifdef CONFIG_PM_SLEEP > +static int amd_mp2_pci_device_suspend(struct pci_dev *pci_dev, > + pm_message_t mesg) > +{ > + int ret; > + struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev); > + > + if (!privdata) > + return -EINVAL; > + > + ret = pci_save_state(pci_dev); > + if (ret) { > + dev_err(ndev_dev(privdata), > + "pci_save_state failed = %d\n", ret); > + return ret; > + } > + > + pci_enable_wake(pci_dev, PCI_D3hot, 0); > + pci_disable_device(pci_dev); > + pci_set_power_state(pci_dev, pci_choose_state(pci_dev, mesg)); > + > + return 0; > +} > + > +static int amd_mp2_pci_device_resume(struct pci_dev *pci_dev) > +{ > + struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev); > + > + if (!privdata) > + return -EINVAL; > + > + pci_set_power_state(pci_dev, PCI_D0); > + pci_restore_state(pci_dev); > + > + if (pci_enable_device(pci_dev) < 0) { > + dev_err(ndev_dev(privdata), "pci_enable_device failed\n"); > + return -EIO; > + } > + > + pci_enable_wake(pci_dev, PCI_D3hot, 0); > + > + return 0; > +} > +#endif > + > +static struct pci_driver amd_mp2_pci_driver = { > + .name = DRIVER_NAME, > + .id_table = amd_mp2_pci_tbl, > + .probe = amd_mp2_pci_probe, > + .remove = amd_mp2_pci_remove, > +#ifdef CONFIG_PM_SLEEP > + .suspend = amd_mp2_pci_device_suspend, > + .resume = amd_mp2_pci_device_resume, > +#endif > +}; > + > +static int amd_mp2_device_match(struct device *dev, void *data) > +{ > + struct pci_dev *candidate = data; > + > + if (!candidate) > + return 1; > + return (to_pci_dev(dev) == candidate) ? 1 : 0; > +} > + > +struct amd_mp2_dev *amd_mp2_find_device(struct pci_dev *candidate) > +{ > + struct device *dev; > + struct pci_dev *pci_dev; > + > + dev = driver_find_device(&amd_mp2_pci_driver.driver, NULL, candidate, > + amd_mp2_device_match); > + if (!dev && candidate) > + dev = driver_find_device(&amd_mp2_pci_driver.driver, NULL, NULL, > + amd_mp2_device_match); > + if (!dev) > + return NULL; > + > + pci_dev = to_pci_dev(dev); > + return (struct amd_mp2_dev *)pci_get_drvdata(pci_dev); > +} > +EXPORT_SYMBOL_GPL(amd_mp2_find_device); > + > +static int __init amd_mp2_pci_driver_init(void) > +{ > + if (debugfs_initialized()) > + debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL); > + > + return pci_register_driver(&amd_mp2_pci_driver); > +} > +module_init(amd_mp2_pci_driver_init); > + > +static void __exit amd_mp2_pci_driver_exit(void) > +{ > + pci_unregister_driver(&amd_mp2_pci_driver); > + debugfs_remove_recursive(debugfs_dir); > +} > +module_exit(amd_mp2_pci_driver_exit); > + > +MODULE_DESCRIPTION(DRIVER_DESC); > +MODULE_VERSION(DRIVER_VER); > +MODULE_AUTHOR("Shyam Sundar S K <shyam-sundar....@amd.com>"); > +MODULE_AUTHOR("Elie Morisse <syniu...@gmail.com>"); > +MODULE_LICENSE("Dual BSD/GPL"); > diff --git a/drivers/i2c/busses/i2c-amd-pci-mp2.h > b/drivers/i2c/busses/i2c-amd-pci-mp2.h > new file mode 100644 > index 000000000000..65601b6ba3b3 > --- /dev/null > +++ b/drivers/i2c/busses/i2c-amd-pci-mp2.h > @@ -0,0 +1,224 @@ > +/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ > +/* > + * AMD PCIe MP2 Communication Driver > + * > + * Authors: Shyam Sundar S K <shyam-sundar....@amd.com> > + * Elie Morisse <syniu...@gmail.com> > + */ > + > +#ifndef I2C_AMD_PCI_MP2_H > +#define I2C_AMD_PCI_MP2_H > + > +#include <linux/pci.h> > + > +#define PCI_DEVICE_ID_AMD_MP2 0x15E6 > + > +struct amd_i2c_common; > +struct amd_mp2_dev; > + > +enum { > + /* MP2 C2P Message Registers */ > + AMD_C2P_MSG0 = 0x10500, /* MP2 Message for I2C0 */ > + AMD_C2P_MSG1 = 0x10504, /* MP2 Message for I2C1 */ > + AMD_C2P_MSG2 = 0x10508, /* DRAM Address Lo / Data 0 */ > + AMD_C2P_MSG3 = 0x1050c, /* DRAM Address HI / Data 1 */ > + AMD_C2P_MSG4 = 0x10510, /* Data 2 */ > + AMD_C2P_MSG5 = 0x10514, /* Data 3 */ > + AMD_C2P_MSG6 = 0x10518, /* Data 4 */ > + AMD_C2P_MSG7 = 0x1051c, /* Data 5 */ > + AMD_C2P_MSG8 = 0x10520, /* Data 6 */ > + AMD_C2P_MSG9 = 0x10524, /* Data 7 */ > + > + /* MP2 P2C Message Registers */ > + AMD_P2C_MSG0 = 0x10680, /* Do not use */ > + AMD_P2C_MSG1 = 0x10684, /* I2C0 interrupt register */ > + AMD_P2C_MSG2 = 0x10688, /* I2C1 interrupt register */ > + AMD_P2C_MSG3 = 0x1068C, /* MP2 debug info */ > + AMD_P2C_MSG_INTEN = 0x10690, /* MP2 interrupt gen register */ > + AMD_P2C_MSG_INTSTS = 0x10694, /* Interrupt status */ > +}; > + > +/* Command register data structures */ > + > +#define i2c_none (-1) > +enum i2c_cmd { > + i2c_read = 0, > + i2c_write, > + i2c_enable, > + i2c_disable, > + number_of_sensor_discovered, > + is_mp2_active, > + invalid_cmd = 0xF, > +}; > + > +enum speed_enum { > + speed100k = 0, > + speed400k = 1, > + speed1000k = 2, > + speed1400k = 3, > + speed3400k = 4 > +}; > + > +enum mem_type { > + use_dram = 0, > + use_c2pmsg = 1, > +}; > + > +/** > + * union i2c_cmd_base : bit access of C2P commands > + * @i2c_cmd: bit 0..3 i2c R/W command > + * @bus_id: bit 4..7 i2c bus index > + * @slave_addr: bit 8..15 slave address > + * @length: bit 16..27 read/write length > + * @i2c_speed: bit 28..30 bus speed > + * @mem_type: bit 31 0-DRAM; 1-C2P msg o/p > + */ > +union i2c_cmd_base { > + u32 ul; > + struct { > + enum i2c_cmd i2c_cmd : 4; > + u8 bus_id : 4; > + u32 slave_addr : 8; > + u32 length : 12; > + enum speed_enum i2c_speed : 3; > + enum mem_type mem_type : 1; > + } s; > +}; > + > +/* Response - Response of SFI */ > +enum response_type { > + invalid_response = 0, > + command_success = 1, > + command_failed = 2, > +}; > + > +/* Status - Command ID to indicate a command */ > +enum status_type { > + i2c_readcomplete_event = 0, > + i2c_readfail_event = 1, > + i2c_writecomplete_event = 2, > + i2c_writefail_event = 3, > + i2c_busenable_complete = 4, > + i2c_busenable_failed = 5, > + i2c_busdisable_complete = 6, > + i2c_busdisable_failed = 7, > + invalid_data_length = 8, > + invalid_slave_address = 9, > + invalid_i2cbus_id = 10, > + invalid_dram_addr = 11, > + invalid_command = 12, > + mp2_active = 13, > + numberof_sensors_discovered_resp = 14, > + i2c_bus_notinitialized > +}; > + > +/** > + * union i2c_event : bit access of P2C events > + * @response: bit 0..1 i2c response type > + * @status: bit 2..6 status_type > + * @mem_type: bit 7 0-DRAM; 1-C2P msg o/p > + * @bus_id: bit 8..11 i2c bus id > + * @length: bit 12..23 message length > + * @slave_addr: bit 24-31 slave address > + */ > +union i2c_event { > + u32 ul; > + struct { > + enum response_type response : 2; > + enum status_type status : 5; > + enum mem_type mem_type : 1; > + u8 bus_id : 4; > + u32 length : 12; > + u32 slave_addr : 8; > + } r; > +}; > + > +/** > + * struct i2c_rw_config - i2c read/write settings > + * @slave_addr: slave address > + * @length: message length > + * @buf: buffer address > + * @dma_addr: if length > 32, holds the DMA buffer address > + * @dma_direction: if length > 32, is either FROM or TO device > + */ > +struct i2c_rw_config { > + u16 slave_addr; > + u32 length; > + u32 *buf; > + dma_addr_t dma_addr; > + enum dma_data_direction dma_direction; > +}; > + > +/** > + * struct amd_i2c_pci_ops - platdrv hooks > + */ > +struct amd_i2c_pci_ops { > + int (*read_complete)(union i2c_event *event); > + int (*write_complete)(union i2c_event *event); > + int (*connect_complete)(union i2c_event *event); > +}; > + > +/** > + * struct amd_i2c_common - per bus/i2c adapter context, shared > + * between the pci and the platform driver > + * @eventval: MP2 event value set by the IRQ handler to be processed > + * by the worker > + * @ops: platdrv hooks > + * @rw_cfg: settings for reads/writes > + * @work: delayed worker struct > + * @reqcmd: i2c command type requested by platdrv > + * @requested: true if the interrupt answered a request from platdrv > + * @bus_id: bus index > + * @i2c_speed: i2c bus speed determined by the slowest slave > + */ > +struct amd_i2c_common { > + union i2c_event eventval; > + const struct amd_i2c_pci_ops *ops; > + struct amd_mp2_dev *mp2_dev; > + struct i2c_rw_config rw_cfg; > + struct delayed_work work; > + enum i2c_cmd reqcmd; > + u8 bus_id; > + enum speed_enum i2c_speed; > +}; > + > +/** > + * struct amd_mp2_dev - per PCI device context > + * @pci_dev: PCI driver node > + * @plat_common: MP2 devices may have up to two busses, > + * each bus corresponding to an i2c adapter > + * @mmio: iommapped registers > + * @lock: interrupt spinlock > + * @c2p_lock: controls access to the C2P mailbox shared between > + * the two adapters > + */ > +struct amd_mp2_dev { > + struct pci_dev *pci_dev; > + struct amd_i2c_common *plat_common[2]; > + void __iomem *mmio; > + raw_spinlock_t lock; > + struct mutex c2p_lock; > + struct dentry *debugfs_dir; > + struct dentry *debugfs_info; > +}; > + > +int amd_mp2_read(struct amd_i2c_common *i2c_common); > +int amd_mp2_write(struct amd_i2c_common *i2c_common); > +int amd_mp2_connect(struct amd_i2c_common *i2c_common, bool enable); > + > +int amd_i2c_register_cb(struct amd_mp2_dev *mp2_dev, > + struct amd_i2c_common *i2c_common); > +int amd_i2c_unregister_cb(struct amd_mp2_dev *mp2_dev, > + struct amd_i2c_common *i2c_common); > + > +struct amd_mp2_dev *amd_mp2_find_device(struct pci_dev *candidate); > + > +#define ndev_pdev(ndev) ((ndev)->pci_dev) > +#define ndev_name(ndev) pci_name(ndev_pdev(ndev)) > +#define ndev_dev(ndev) (&ndev_pdev(ndev)->dev) > +#define work_amd_i2c_common(__work) \ > + container_of(__work, struct amd_i2c_common, work.work) > +#define event_amd_i2c_common(__event) \ > + container_of(__event, struct amd_i2c_common, eventval) > + > +#endif > diff --git a/drivers/i2c/busses/i2c-amd-plat-mp2.c > b/drivers/i2c/busses/i2c-amd-plat-mp2.c > new file mode 100644 > index 000000000000..a10bd08fe1db > --- /dev/null > +++ b/drivers/i2c/busses/i2c-amd-plat-mp2.c > @@ -0,0 +1,373 @@ > +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause > +/* > + * AMD MP2 I2C Platform Driver > + * > + * Authors: Nehal Bakulchandra Shah <nehal-bakulchandra.s...@amd.com> > + * Elie Morisse <syniu...@gmail.com> > + */ > + > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/types.h> > +#include <linux/slab.h> > +#include <linux/i2c.h> > +#include <linux/platform_device.h> > +#include <linux/acpi.h> > +#include <linux/delay.h> > + > +#include "i2c-amd-pci-mp2.h" > +#define DRIVER_NAME "i2c-amd-plat-mp2" > + > +#define AMD_MP2_I2C_MAX_RW_LENGTH ((1 << 12) - 1) > +#define AMD_I2C_TIMEOUT (msecs_to_jiffies(250)) > + > +/** > + * struct amd_i2c_dev - MP2 bus/i2c adapter context > + * @i2c_common: shared context with the MP2 pci driver > + * @pdev: platform driver node > + * @adapter: i2c adapter > + * @xfer_lock: xfer lock > + * @completion: xfer completion object > + */ > +struct amd_i2c_dev { > + struct amd_i2c_common i2c_common; > + struct platform_device *pdev; > + struct i2c_adapter adapter; > + struct mutex xfer_lock; > + struct completion msg_complete; > + struct i2c_msg *msg_buf; > + bool is_configured; > +}; > + > +static const struct i2c_adapter_quirks amd_i2c_dev_quirks = { > + .max_read_len = AMD_MP2_I2C_MAX_RW_LENGTH, > + .max_write_len = AMD_MP2_I2C_MAX_RW_LENGTH, > +}; > + > +#define amd_i2c_dev_common(__common) \ > + container_of(__common, struct amd_i2c_dev, i2c_common) > + > +static int i2c_amd_read_completion(union i2c_event *event) > +{ > + struct amd_i2c_common *i2c_common = event_amd_i2c_common(event); > + struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common); > + > + if (event->r.status == i2c_readcomplete_event) > + dev_dbg(&i2c_dev->pdev->dev, "%s readdata:%*ph\n", > + __func__, event->r.length, > + i2c_common->rw_cfg.buf); > + > + complete(&i2c_dev->msg_complete); > + > + return 0; > +} > + > +static int i2c_amd_write_completion(union i2c_event *event) > +{ > + struct amd_i2c_common *i2c_common = event_amd_i2c_common(event); > + struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common); > + > + complete(&i2c_dev->msg_complete); > + > + return 0; > +} > + > +static int i2c_amd_connect_completion(union i2c_event *event) > +{ > + struct amd_i2c_common *i2c_common = event_amd_i2c_common(event); > + struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common); > + > + complete(&i2c_dev->msg_complete); > + > + return 0; > +} > + > +static const struct amd_i2c_pci_ops data_handler = { > + .read_complete = i2c_amd_read_completion, > + .write_complete = i2c_amd_write_completion, > + .connect_complete = i2c_amd_connect_completion, > +}; > + > +static int i2c_amd_pci_configure(struct amd_i2c_dev *i2c_dev) > +{ > + struct amd_i2c_common *i2c_common = &i2c_dev->i2c_common; > + > + amd_i2c_register_cb(i2c_common->mp2_dev, i2c_common); > + i2c_common->ops = &data_handler; > + > + return 0; > +} > + > +static int i2c_amd_pci_xconnect(struct amd_i2c_dev *i2c_dev, bool enable) > +{ > + struct amd_i2c_common *i2c_common = &i2c_dev->i2c_common; > + unsigned long timeout; > + > + reinit_completion(&i2c_dev->msg_complete); > + amd_mp2_connect(i2c_common, enable); > + timeout = wait_for_completion_timeout(&i2c_dev->msg_complete, > + AMD_I2C_TIMEOUT); > + if (timeout == 0) { > + dev_err(&i2c_dev->pdev->dev, > + "i2c connection timed out\n"); > + mutex_unlock(&i2c_dev->xfer_lock); > + return -ETIMEDOUT; > + } > + > + return 0; > +} > + > +static int i2c_amd_xfer_msg(struct amd_i2c_dev *i2c_dev, struct i2c_msg > *pmsg) > +{ > + struct amd_i2c_common *i2c_common = &i2c_dev->i2c_common; > + unsigned long timeout; > + bool is_read = pmsg->flags & I2C_M_RD; > + > + reinit_completion(&i2c_dev->msg_complete); > + > + i2c_common->rw_cfg.slave_addr = pmsg->addr; > + i2c_common->rw_cfg.buf = (u32 *)pmsg->buf; > + i2c_common->rw_cfg.length = pmsg->len; > + i2c_dev->msg_buf = pmsg; > + > + if (is_read) > + amd_mp2_read(i2c_common); > + else > + amd_mp2_write(i2c_common); > + > + timeout = wait_for_completion_timeout > + (&i2c_dev->msg_complete, AMD_I2C_TIMEOUT); > + if (timeout == 0) { > + dev_err(&i2c_dev->pdev->dev, > + "i2c %s timed out\n", > + is_read ? "read" : "write"); > + return -ETIMEDOUT; > + } > + > + return 0; > +} > + > +static int i2c_amd_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int > num) > +{ > + struct amd_i2c_dev *dev = i2c_get_adapdata(adap); > + int i; > + struct i2c_msg *pmsg; > + int err; > + > + mutex_lock(&dev->xfer_lock); > + > + if (dev->is_configured == 0) { > + i2c_amd_pci_configure(dev); > + i2c_amd_pci_xconnect(dev, true); > + dev->is_configured = 1; > + } > + > + for (i = 0; i < num; i++) { > + pmsg = &msgs[i]; > + err = i2c_amd_xfer_msg(dev, pmsg); > + if (err) > + break; > + } > + > + mutex_unlock(&dev->xfer_lock); > + > + if (err) > + return err; > + return num; > +} > + > +static u32 i2c_amd_func(struct i2c_adapter *a) > +{ > + return I2C_FUNC_I2C; > +} > + > +static const struct i2c_algorithm i2c_amd_algorithm = { > + .master_xfer = i2c_amd_xfer, > + .functionality = i2c_amd_func, > +}; > + > +static enum speed_enum i2c_amd_get_bus_speed(struct platform_device *pdev) > +{ > + u32 acpi_speed; > + int i; > + static const u32 supported_speeds[] = { > + 0, 100000, 400000, 1000000, 1400000, 3400000 > + }; > + > + acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev); > + /* round down to the lowest standard speed */ > + for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) { > + if (acpi_speed < supported_speeds[i]) > + break; > + } > + acpi_speed = supported_speeds[i - 1]; > + > + switch (acpi_speed) { > + case 100000: > + return speed100k; > + case 400000: > + return speed400k; > + case 1000000: > + return speed1000k; > + case 1400000: > + return speed1400k; > + case 3400000: > + return speed3400k; > + default: > + return speed400k; > + } > +} > + > +static struct device *i2c_amd_acpi_get_first_phys_node(struct acpi_device > *adev) > +{ > + const struct acpi_device_physical_node *node; > + > + if (list_empty(&adev->physical_node_list)) > + return NULL; > + > + node = list_first_entry(&adev->physical_node_list, > + struct acpi_device_physical_node, node); > + return node->dev; > +} > + > +/* > + * Assume that the first device listed by the _DEP method is the parent > + * MP2 device > + */ > +static struct pci_dev *i2c_amd_find_pci_parent(struct acpi_device *adev) > +{ > + struct acpi_device *parent_adev; > + struct device *phys_dev; > + struct acpi_handle_list dep_devices; > + acpi_status status; > + > + if (!acpi_has_method(adev->handle, "_DEP")) > + return NULL; > + > + status = acpi_evaluate_reference(adev->handle, "_DEP", NULL, > + &dep_devices); Several other callers of acpi_evaluate_reference() do call acpi_has_method() first, but I'm pretty sure that's not necessary. If _DEP doesn't exist, acpi_evaluate_reference() should return an error itself. _DEP is for operation region dependencies. I don't know enough about ACPI to know why you're using it to find the PCI device related to an ACPI device. That doesn't really seem like an op region thing. > + if (ACPI_FAILURE(status) || !dep_devices.count) > + return NULL; > + > + if (acpi_bus_get_device(dep_devices.handles[0], &parent_adev)) > + return NULL; > + phys_dev = i2c_amd_acpi_get_first_phys_node(parent_adev); > + > + if (!dev_is_pci(phys_dev)) > + return NULL; > + return to_pci_dev(phys_dev); > +} > + > +static int i2c_amd_probe(struct platform_device *pdev) > +{ > + int ret; > + struct amd_i2c_dev *i2c_dev; > + struct device *dev = &pdev->dev; > + acpi_handle handle = ACPI_HANDLE(&pdev->dev); > + struct acpi_device *adev; > + struct pci_dev *parent_candidate = NULL; > + > + i2c_dev = devm_kzalloc(dev, sizeof(*i2c_dev), GFP_KERNEL); > + if (!i2c_dev) > + return -ENOMEM; > + > + i2c_dev->pdev = pdev; > + > + if (!acpi_bus_get_device(handle, &adev)) { > + const char *uid = adev->pnp.unique_id; > + > + if (!uid) { > + dev_err(&pdev->dev, "missing UID/bus id!\n"); > + return -EINVAL; > + } > + > + if (strcmp(uid, "0") == 0) { > + i2c_dev->i2c_common.bus_id = 0; > + } else if (strcmp(uid, "1") == 0) { > + i2c_dev->i2c_common.bus_id = 1; > + } else { > + dev_err(&pdev->dev, > + "incorrect UID/bus id \"%s\"!\n", uid); > + return -EINVAL; > + } > + > + dev_dbg(&pdev->dev, "bus id is %u\n", > + i2c_dev->i2c_common.bus_id); > + > + i2c_dev->i2c_common.i2c_speed = i2c_amd_get_bus_speed(pdev); > + } else { > + i2c_dev->i2c_common.i2c_speed = speed400k; > + } > + > + /* setup i2c adapter description */ > + i2c_dev->adapter.owner = THIS_MODULE; > + i2c_dev->adapter.algo = &i2c_amd_algorithm; > + i2c_dev->adapter.quirks = &amd_i2c_dev_quirks; > + i2c_dev->adapter.dev.parent = dev; > + i2c_dev->adapter.algo_data = i2c_dev; > + ACPI_COMPANION_SET(&i2c_dev->adapter.dev, ACPI_COMPANION(&pdev->dev)); > + i2c_dev->adapter.dev.of_node = dev->of_node; > + snprintf(i2c_dev->adapter.name, sizeof(i2c_dev->adapter.name), "%s-%s", > + "i2c_dev-i2c", dev_name(pdev->dev.parent)); > + > + if (adev) > + parent_candidate = i2c_amd_find_pci_parent(adev); > + i2c_dev->i2c_common.mp2_dev = amd_mp2_find_device(parent_candidate); > + if (!i2c_dev->i2c_common.mp2_dev) { > + dev_err(&pdev->dev, > + "%s Could not find MP2 PCI device for i2c adapter\n", > + __func__); > + return -EINVAL; > + } > + > + platform_set_drvdata(pdev, i2c_dev); > + > + i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); > + > + init_completion(&i2c_dev->msg_complete); > + mutex_init(&i2c_dev->xfer_lock); > + > + /* and finally attach to i2c layer */ > + ret = i2c_add_adapter(&i2c_dev->adapter); > + > + if (ret < 0) > + dev_err(&pdev->dev, "i2c add adapter failed = %d\n", ret); > + > + return ret; > +} > + > +static int i2c_amd_remove(struct platform_device *pdev) > +{ > + struct amd_i2c_dev *i2c_dev = platform_get_drvdata(pdev); > + struct amd_i2c_common *i2c_common = &i2c_dev->i2c_common; > + > + i2c_amd_pci_xconnect(i2c_dev, false); > + > + amd_i2c_unregister_cb(i2c_common->mp2_dev, i2c_common); > + i2c_del_adapter(&i2c_dev->adapter); > + > + return 0; > +} > + > +static const struct acpi_device_id i2c_amd_acpi_match[] = { > + { "AMDI0011" }, > + { }, > +}; > +MODULE_DEVICE_TABLE(acpi, i2c_amd_acpi_match); > + > +static struct platform_driver amd_i2c_plat_driver = { > + .probe = i2c_amd_probe, > + .remove = i2c_amd_remove, > + .driver = { > + .name = "i2c_amd_plat_mp2", > + .acpi_match_table = ACPI_PTR > + (i2c_amd_acpi_match), > + }, > +}; > + > +module_platform_driver(amd_i2c_plat_driver); > + > +MODULE_DESCRIPTION("AMD MP2 I2C Platform Driver"); > +MODULE_AUTHOR("Nehal Shah <nehal-bakulchandra.s...@amd.com>"); > +MODULE_AUTHOR("Elie Morisse <syniu...@gmail.com>"); > +MODULE_LICENSE("Dual BSD/GPL"); > -- > 2.17.1 >
